BSC does not play nicely with enums whose labels do not start at 0 and
increase linearly. Instead, in such cases, it generates a whole bunch of
conditions to "legalise" any read values, which causes an explosion of
logic in places like the ROB. Thus, use this ugly (but still typed)
alternative that, other than naming conventions enforced by BSC, looks
almost the same as an enum.
This required makeing the Exception type wider by one.
The actual "inBounds" check is currently implemented in the reorder buffer rows, which duplicates the logic ~80 times (number of outstanding instructions), which isn't ideal, but it's using the quick in-bounds check that only compares the mantissa-sized things.
This includes renaming Fifo.bsv to Fifos.bsv to account for a case insensitive file system which confuses this library with FIFO.bsv.
Also this includes an update of the verilator flags that are needed for modern verilator.
Finally, some verilator flag changes for building with LLVM.
Two of these were not properly restricted as read-only from CSRRX instructions,
and there was a bug in the WARL function for writing MIP,
and there was a bug in the TV-reporting of MIP updates.
When a CSRRx instruction writes to FCSR/FFLAGS/FRM, the CPU also
changes MSTATUS.FS and, by implication, MSTATUS.SD because the
floating point state has become "dirty". Tandem Verification
trace-generation was not reporting this update.
MIP/MIE/SIP/SIE fields are WARL (Write-Any/Read-Legal). The CSR
register forces the user-privilege bits ([8,4,0]) to 0 since riscy-ooo
does not support user-level interrupts. However, function
Csrfile.fv_warl_xform() was not mirroring this correctly.
(1) riscy-ooo was mapping all unimplemented CSRs to a benign, user-privilege read-write CSR
Instead, we now catch this RenameStage and steer it to a trap.
(2) MSTATUS.FS was initialized to 2'b00 (absent/off); should be 2'b01 (present and initial)
src_Core/CPU/CsrFile.bsv
Various fixes for WARL'd values of mstatus and sstatus, medeleg,
Added tval field in Trap_Updates returned by csrf.trap
src_Core/Core/Trace_Data2.bsv
Added fields for store_data and store_data_BE
src_Core/Core/Trace_Data2_to_Trace_Data.bsv
Added treatment of store_data and store_data_BE
Fixed bug in next_pc for mkTrace_RET
src_Core/RISCY_OOO/procs/RV64G_OOO/CommitStage.bsv
Fixed Trace_Data2 struct to TV for pc in case of xRET, and tval in case of trap
src_Core/RISCY_OOO/procs/RV64G_OOO/MemExePipeline.bsv
Added store_data and store_data_BE in calls to rob_setExecuted_doFinishMem
src_Core/RISCY_OOO/procs/lib/ReorderBuffer.bsv
Added store_data and store_data_BE in methods rob_setExecuted_doFinishMem
Now handling all Alu and Fpu pipeline outputs, traps and xRets.
Still todo:
(1) Mem pipeline outputs (Ld, Lr/Sc, Amo outputs to dest reg)
(2) For CSRRx, currently reporting WARL pre-write updates; needs to be WARL'd update.
Rd value (destination register) of Integer ops supported
Trap updates (priv and CSR updates) supported.
Still pending: Memory ops Rd value, Fpu Rd value
Now able to run multiple ISA tests in a single simulation run
connected to remote debugger DSharp, using either hart_reset or
ndm_reset between tests to bring the system back into reset state.
All Debug Module commands working:
- dm_reset, hart_reset, ndm_reset
- break (set breakpoint)
- step
- continue (until breakpoint of 'halt' command)
- halt
- read/write GPR, FPR, CSR, memory
- elf_load
After a test, GDB can write DCSR to restore to Machine privilege,
write to PC (DPC) to restore boot value,
write MSTATUS to restore to initial value,
then can load and run next test.
Modified:
src_Core/CPU/CsrFile.bsv
Modified method 'trap' to use 'addr' for trap_val (MTVAL) instead of PC
for InstAccessFault and InstPageFault
src_Core/RISCY_OOO/procs/RV64G_OOO/FetchStage.bsv
Added 'tval' field to Fetch2Fetch3; set the value on TLB faults; send it out in 'FromFetchStage' struct
src_Core/RISCY_OOO/procs/RV64G_OOO/RenameStage.bsv
In rule doRenamingTrap, pass tval from FromFetchStage struct to ToReorderBuffer struct
src_Core/RISCY_OOO/procs/lib/ReorderBuffer.bsv
Add 'tval' Ehr to reorderbuffer slot, to accompany 'trap' Ehr.
In method write_enq, store tval from ToReorderBuffer arg into tval Ehr.
In method read_deq, send 'tval' Ehr value into 'ToReorderBuffer' output (goes to CommitStage)
src_Core/RISCY_OOO/procs/RV64G_OOO/CommitStage.bsv
Modified rule doCommitTrap_flush to take tval from 'ToReorderBuffer' input from ROB,
for InstAccessFault and InstPageFault
LICENSE
README.md
Clarified licensing of MIT code and Bluespec code
Tests/Run_regression.py
Emptied out 'exclude_list'
builds/RV64ADFIMSU_Toooba_verilator/Makefile
Added 'C' to Makefile
New method 'debug_external_interrupt_req' to support emulation of a
debug module starts at P3_Core interface and is plumbed all the way in
to the CSR register MIP as interrupt [14]. The corresponding MIE[14]
is always 1, so it is never masked. Still todo: should not be masked
by MSTATUS interrupt-enables either. Also expanded
interrupt-detection logic, mcause etc. to extend up to interrupt 14.
Builds in standalone mode, runs ISA tests.
Builds in src_SSITH_P3, generating RTL.
